Beneficial

Restore or create species-rich, semi-natural grassland

1Twenty studies (including three randomized, replicated, controlled trials) from six countries found restored species-rich, semi-natural grasslands had similar invertebrate, plant or bird diversity or abundance to other grasslands. Seven studies (two randomized, replicated, controlled trials) from five countries found no clear effect on plant or invertebrate numbers, three replicated studies (of which two site comparisons) from two countries found negative effects. Forty studies (including six randomized, replicated, controlled trials) from nine countries identified effective techniques for restoring species-rich grassland. Assessment: beneficial (effectiveness 100 %; certainty 73 %).

2http://www.conservationevidence.com/actions/133

Use mowing techniques to reduce mortality

3Seven studies (including two replicated trials, one controlled and one randomized) from Germany, Ireland, Switzerland and the UK found mowing techniques that reduced mortality or injury in amphibians, birds, invertebrates or mammals. A review found the UK corncrake population increased around the same time that Corncrake Friendly Mowing was introduced and a replicated trial found mowing from the field centre outwards reduced corncrake chick mortality. Assessment: beneficial (effectiveness 100 %; certainty 78 %).

4http://www.conservationevidence.com/actions/698

Likely to be beneficial

Delay mowing or first grazing date on grasslands

5Eight studies (including a European systematic review) from the Netherlands, Sweden and the UK found delaying mowing or grazing benefited some or all plants, invertebrates or birds, including increases in numbers or productivity. Three reviews found the UK corncrake population increased following management that included delayed mowing. Six studies (including a European systematic review) from five countries found no clear effect on some plants, invertebrates or birds. Assessment: likely to be beneficial (effectiveness 60 %; certainty 45 %).

6http://www.conservationevidence.com/actions/131

Leave uncut strips of rye grass on silage fields

7Four studies (including two replicated, controlled trials) from the UK found uncut strips of rye grass benefited some birds, with increased numbers. A randomized, replicated, controlled study from the UK found higher ground beetle diversity on uncut silage plots, but only in the third study year. Assessment: likely to be beneficial (effectiveness 80 %; certainty 49 %).

8http://www.conservationevidence.com/actions/132

Maintain species-rich, semi-natural grassland

9Nine studies (including two randomized, replicated before-and-after trials) from Switzerland and the UK looked at the effectiveness of agri-environment schemes in maintaining species-rich grassland and all except one found mixed results. All twelve studies (including a systematic review) from six countries looking at grassland management options found techniques that improved or maintained vegetation quality. A site comparison from Finland and Russia found butterfly communities were more affected by grassland age and origin than present management. Assessment: likely to be beneficial (effectiveness 80 %; certainty 60 %).

10http://www.conservationevidence.com/actions/702

Maintain traditional water meadows (includes management for breeding and/or wintering waders/ waterfowl)

11Four studies (including a replicated site comparison) from Belgium, Germany, the Netherlands and the UK found maintaining traditional water meadows increased numbers of some birds or plant diversity. One bird species declined. Two studies (including a replicated site comparison from the Netherlands) found mixed or inconclusive effects on birds, plants or wildlife generally. A replicated study from the UK found productivity of one wading bird was too low to sustain populations in some areas of wet grassland managed for wildlife. Assessment: likely to be beneficial (effectiveness 56 %; certainty 50 %).

12http://www.conservationevidence.com/actions/696

Maintain upland heath/moorland

13Eight studies (including one randomized, replicated, controlled trial) from the UK found management, including reducing grazing, can help to maintain the conservation value of upland heath or moorland. Benefits included increased numbers of plants or invertebrates. Three studies (including a before-and-after trial) from the UK found management to maintain upland heath or moorland had mixed effects on some wildlife groups. Four studies (including a controlled site comparison) from the UK found reducing grazing had negative impacts on soil organisms, but a randomized, replicated before-and-after study found heather cover declined where grazing intensity had increased. Assessment: likely to be beneficial (effectiveness 90 %; certainty 50 %).

14http://www.conservationevidence.com/actions/647

Reduce management intensity on permanent grasslands (several interventions at once)

15Eleven studies (including four replicated site comparisons) from three countries found reducing management intensity benefited plants. Sixteen studies (including four paired site comparisons) from four countries found benefits to some or all invertebrates. Five studies (including one paired, replicated site comparison) from four countries found positive effects on some or all birds. Twenty-one studies (including two randomized, replicated, controlled trials) from six countries found no clear effects of reducing management intensity on some or all plants, invertebrates or birds. Five studies (including two paired site comparisons) from four countries found negative effects on plants, invertebrates or birds. Assessment: likely to be beneficial (effectiveness 100 %; certainty 60 %).

16http://www.conservationevidence.com/actions/69

Restore or create traditional water meadows

17Three studies (two before-and-after trials) from Sweden and the UK looked at bird numbers following water meadow restoration, one found increases, one found increases and decreases, one found no increases. Seventeen studies (two randomized, replicated, controlled) from six countries found successful techniques for restoring wet meadow plant communities. Three studies (one replicated, controlled) from four countries found restoration of wet meadow plant communities had reduced or limited success. Assessment: likely to be beneficial (effectiveness 100 %; certainty 50 %).

18http://www.conservationevidence.com/actions/119

Unknown effectiveness (limited evidence)

Add yellow rattle seed Rhinanthus minor to hay meadows

19A review from the UK reported that hay meadows had more plant species when yellow rattle was present. A randomized, replicated controlled trial in the UK found yellow rattle could be established by ‘slot seeding’. Assessment: unknown effectiveness — limited evidence (effectiveness 70 %; certainty 20 %).

20http://www.conservationevidence.com/actions/129

Employ areas of semi-natural habitat for rough grazing (includes salt marsh, lowland heath, bog, fen)

21Three studies (two replicated) from the UK and unspecified European countries found grazing had positive effects on birds, butterflies or biodiversity generally. A series of site comparisons from the UK found one bird species used heathland managed for grazing as feeding but not nesting sites. Two studies (one replicated site comparison) from the UK found grazing had negative effects on two bird species. Assessment: unknown effectiveness — limited evidence (effectiveness 20 %; certainty 10 %).

22http://www.conservationevidence.com/actions/697

Exclude livestock from semi-natural habitat (including woodland)

23Three studies (including one randomized, replicated, controlled trial) from Ireland and the UK found excluding livestock from semi-natural habitats benefited plants and invertebrates. Three studies (one replicated, controlled and one replicated paired sites comparison) from Ireland and the UK did not find benefits to plants or birds. Two studies (one replicated, controlled and a review) from Poland and the UK found limited or mixed effects. Assessment: unknown effectiveness — limited evidence (effectiveness 20 %; certainty 15 %).

24http://www.conservationevidence.com/actions/150

Maintain wood pasture and parkland

25A randomized, replicated, controlled trial in Sweden found annual mowing on wood pasture maintained the highest number of plant species. Assessment: unknown effectiveness — limited evidence (effectiveness 40 %; certainty 10 %).

26http://www.conservationevidence.com/actions/649

Plant cereals for whole crop silage

27A replicated study from the UK found cereal-based whole crop silage had higher numbers of some birds than other crops. A review from the UK reported that seed-eating birds avoided cereal-based whole crop silage in winter, but used it as much as spring barley in summer. Assessment: unknown effectiveness — limited evidence (effectiveness 80 %; certainty 28 %).

28http://www.conservationevidence.com/actions/149

Raise mowing height on grasslands

29Three studies (including one replicated, controlled trial) from the UK or unspecified European countries found raised mowing heights caused less damage to amphibians and invertebrates or increased Eurasian skylark productivity. Two studies (one randomized, replicated, controlled) from the UK found no effect on bird or invertebrate numbers and a replicated study from the UK found young birds had greater foraging success in shorter grass. Assessment: unknown effectiveness — limited evidence (effectiveness 0 %; certainty 35 %).

30http://www.conservationevidence.com/actions/138

Restore or create upland heath/moorland

31A small trial in northern England found moorland restoration increased the number of breeding northern lapwing. A UK review concluded that vegetation changes were slow during the restoration of heather moorland from upland grassland. Assessment: unknown effectiveness — limited evidence (effectiveness 78 %; certainty 20 %).

32http://www.conservationevidence.com/actions/650

Restore or create wood pasture

33A replicated, controlled trial in Belgium found survival and growth of tree seedlings planted in pasture was enhanced when they were protected from grazing. A replicated study in Switzerland found cattle browsing had negative effects on tree saplings. Assessment: unknown effectiveness — limited evidence (effectiveness 40 %; certainty 5 %).

34http://www.conservationevidence.com/actions/644

Use traditional breeds of livestock

35Three studies (one replicated) from the UK found the breed of livestock affected vegetation structure, invertebrate communities and the amount of plants grazed. A replicated trial from France, Germany and the UK found no difference in the number of plant species or the abundance of birds, invertebrates or mammals between areas grazed by traditional or commercial livestock. Assessment: unknown effectiveness — limited evidence (effectiveness 0 %; certainty 20 %).

36http://www.conservationevidence.com/actions/539

Likely to be ineffective or harmful

Reduce grazing intensity on grassland (including seasonal removal of livestock)

37Fifteen studies (including three randomized, replicated, controlled trials) from four countries found reducing grazing intensity benefited birds, invertebrates or plants. Three studies (including one randomized, replicated, controlled trial) from the Netherlands and the UK found no benefit to plants or invertebrates. Nine studies (including a systematic review) from France, Germany and the UK found mixed effects for some or all wildlife groups. The systematic review concluded that intermediate grazing levels are usually optimal but different wildlife groups are likely to have different grazing requirements. Assessment: likely to be ineffective (effectiveness 30 %; certainty 70 %).

38http://www.conservationevidence.com/actions/704

No evidence found (no assessment)

39We have captured no evidence for the following interventions:

• Maintain rush pastures
• Mark fencing to avoid bird mortality
• Plant brassica fodder crops (grazed in situ)

Evidence not assessed

Create open patches or strips in permanent grassland

40A randomized, replicated, controlled study from the UK found more Eurasian skylarks used fields containing open strips, but numbers varied. A randomized, replicated, controlled study from the UK found insect numbers on grassy headlands initially dropped when strips were cleared. Assessment: this intervention has not been assessed.

41http://www.conservationevidence.com/actions/563

Provide short grass for birds

42A replicated UK study found two bird species spent more time foraging on short grass than longer grass. Assessment: this intervention has not been assessed.

43http://www.conservationevidence.com/actions/115

Use mixed stocking

44A replicated, controlled study in the UK found more spiders, harvestmen and pseudoscorpions in grassland grazed by sheep-only than grassland grazed by sheep and cattle. Differences were only found when suction sampling not pitfall-trapping. Assessment: this intervention has not been assessed.

45http://www.conservationevidence.com/actions/93